Boiler superheater tube reaming assembly



1966 J. w. SPENCER ETAL 3,

BOILER SUPERHEATER TUBE REAMING ASSEMBLY Filed Aug. 20, 1965 F5 Sheets-Sheet 1 INVENTORS JOHN M. SPENCER CLAUDE 6. RICE I fi Nov. 22, 1966 J. w. SPENCER ETAL 3,286,553

BOILER SUPERHEATER TUBE REAMING ASSEMBLY Filed Aug. 20, 1965 5 Sheets-Sheet 2 FIG. 2.

INVENTORS JOHN W. SPENCER LAUDE 0. RICE BY ,5 I I MyM ATTYS,

Nov. 22, 1966 J. w. SPENCER ETAL 3,286,553

BOILER SUPERHEATER TUBE REAMING ASSEMBLY Filed Aug. 20, 1965 5 Sheets-Sheet 5 INVENTORS JOHN W. SPENCER CLAUDE C. RICE 1M ATTYS.

United States Patent 3,286,553 BOILER SUPERHEATER TUBE REAMING 7 Claims. (Cl. 77-2) The invention described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

This invention relates to the removal of boiler or superheater tubes from a tube sheet, and more particularly to an improved reaming apparatus for removing the welded end portion of a tube so as to free it for disassembly with respect to the tube sheet. It is one object of this invention to provide an improved, hand operated reaming apparatus for the removal of the welded end portion of a boiler tube or the like, and which apparatus is notably simple to position and to operate.

Another object of this invention is the provision of tube end reaming apparatus which is particularly rugged in construction and eflicient in use, yet inexpensive to manufacture.

Still another object of this invention is the provision of a novel reaming apparatus which is readily adjustable for use in removal of tubes from tube sheets having different spacing of the tubes.

As another object, this invention aims to accomplish the foregoing through the provision of a cutting or reaming element supported for rotation by a thrust bearing pivotal-1y mounted at one end of a pressure arm, which arm is pivotable in the nature of a first class lever on an adjustable fulcrum means which is adapted to be anchored in a tube other than the one to be removed, and screw means at the other end of the pressure arm and operable against the tube sheet to effect feeding of the reamer element as weld metal is removed thereby.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in the light of the accompanying drawings in which:

FIG. 1 is a side elevational view of a reaming apparatus embodying the invention shown in a position of use;

FIG. 2 is a plan View of the reaming apparatus of FIG. 1;

FIG. 3 is a sectional view of the apparatus taken substantially along line 3-3 of FIG. 1;

FIG. 4 is a sectional view of the apparatus taken substantially along line 44 of FIG. 1; and

FIG. 5 is an enlarged sectional view taken substantially along line 5-5 of FIG. 1.

In the form of the invention illustrated in the drawings and described hereinafter, there is provided a reaming apparatus, generally indicated at 10, which is particularly useful in freeing boiler or superheater tubes 11 from welded connection with a tube sheet 12. This is accomplished by reaming or cutting away the weld metal 13 at the end of the tube.

The apparatus comprises a pressure arm 15 which is bifurcated at one end to provide spaced fingers 16.

Pivotally mounted between the fingers 16, as by rivets 17, is a ring 18 in which is rotatably journalled a shaft 19.

The shaft 19, best illustrated in FIG. 3, is provided with a central flange 20 presenting an axially facing shoulder 21. Disposed between the shoulder 21 and the pivoted ring 18 is a thrust bearing, generally indicated at 22 and which transmits force from the pressure arm to Patented Nov. 22, 1966 "ice shaft 19 while permitting rotation of the latter. In this regard, rotation of the shaft 19 is effected through the agency of a suitable wrench (not shown) applied to a squared end 23 of the shaft 19 projecting beyond the ring 18. The wrench may suitably be a powered drive wrench.

A transverse opening 24, which in this example is square, extends through the shaft 19 and receives a cutting or reaming element 25 which is conveniently fixed in the opening by a set screw 26. The ends of the reaming element 25 extend beyond the shaft 19 and are ground to form cutting edges of a contour which will remove weld metal and a portion of the end of a tube 11 being removed and leave a recess 27 of a desired shape.

The shaft 19 is provided with a reduced end portion 30 extending beyond a shoulder 31. A pilot sleeve 32 is rotatably confined on the shaft end portion 30 between the shoulder 31 and a washer 33 secured to the shaft by a screw 34. The pilot sleeve 32 is inserted into the opening of the tube 11 to be removed and serves as a guide for the shaft during rotation thereof to effect removal of weld metal by the reamer element 25.

The pressure arm 15 is pivotable in the nature of a first class lever on an adjustable fulcrum means, best illustrated in FIG. 4, which is adapted to be anchored in a tube 11 other than the one which is to be removed. The fulcrum means comprises a rod 40 having a threaded end portion 41 extending through an elongated slot 42 in the pressure arm 15. A fulcrum nut 44 is threaded on the end portion 41 so as to slidingly engage the surface of the arm 15 remote from the tube sheet being worked on, and is conveniently locked by a set screw 45.

A washer 46 surrounds the rod 40 and is urged against the arm 15 by a compression spring 47 acting between the washer 46 and a washer 48 which is positioned against a nut 49 engaged on a threaded end portion 50 of the rod. The spring 47 normally holds the arm 15 against the fulcrum nut 44, but permits the rod 40 to be selectively positioned within the slot 42 for adjusting the fulcrum means to a position where the rod 40 may be inserted into a tube 11 other than the one being removed.

The rod 40 is adapted to be anchored in such a tube 11 by means including a segmented, knurled sleeve 52 having, in this example, four segments as is best illustrated in FIG. 5. The segmented sleeve 52, which surrounds the threaded portion 50 of the rod 40 within the tube 11, has an annular recess in which is received a split, spring ring 53 which embraces the segmented sleeve and tends to decrease the effective outside diameter thereof.

The segments of sleeve 52 are adapted to be spread outwardly into tight frictional engagement with the tube 11 by an annular, frustoconical or tapered wedge member which is slideable along the rod 40 and is cooperable with complementary tapered inner surfaces of the segments. To this end, the segmented sleeve 52 is keyed by a suitable key 56 to a nut 57 which is threadedly engaged on the portion 50 of the rod 40, and the end of the rod 40 projecting beyond the nut 44 is squared to receive a suitable wrench for effecting rotation of the rod after the segmented sleeve 52 has been inserted into a tube 11, whereby the threaded portion 50 will run through nut 57 causing nut 49 to force the wedge member 55 into the segmented sleeve, expanding the latter into tight frictional engagement with the tube 11 in which it is located. It will be noted that the nut 57 can be prevented from rotating with the shaft 40 before expansion of the segmented sleeve by canting the rod sufficiently to cause some binding engagement of the sleeve with the tube.

At the end of the arm 15 remote from the pivoted ring 18, the arm is provided with a threaded opening 60 in which is received a feed screw 61. The feed screw 61 is preferably provided with a shoe 62 having a ball and socket connection 63 with the feed screw. The shoe 62 is adapted to bear against the tube sheet 12 and, through the arm 15 and thrust bearing 22, rotation of the screw 61 provides axial thrust to the shaft 19 and reamer element 25. The end 64 of the feed screw 61 remote from the shoe 62 is squared for receiving a suitable wrench (not shown) which may be hand operated and may conveniently be the same wrench as is utilized to turn rod 40.

The arm 15, while made of a relatively rigid material such as steel, has some inherent springiness and therefore only intermittent advancement of the screw is necessary to maintain sufficient thrust on the shaft 19 for the reamer element 25 to work effectively.

Once the weld metal 13 has been reamed away to eliminate the welded connection between the tube 11 and the sheet 12, a punch or drift may be used to drive the freed tube 11 from the tube sheet. When a replacement tube is inserted into the sheet, the recess 27 provides a convenient groove into which a new weld bead may be laid.

From the foregoing detailed description of an exemplary form of reaming apparatus embodying the invention it will be appreciated that the aforementioned objects and advantages, as well as others apparent from this de-# scription, are achieved by the invention.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that within. the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed:

1. Reaming appartus comprising:

a pressure arm having a bifurcated end;

a ring pivotally supported in said bifurcated end;

a shaft rotatably journalled in said ring;

a thrust bearing acting between said shaft and said ring;

a reaming element carried by said shaft for rotation therewith;

fulcrum means adjustably positionable along said pressure arm between the ends thereof and including expansion means for anchoring of said fulcrum means in an opening; and

screw means operative on the end of said pressure arm remote from said bifurcated end for supply feed thrust to said shaft through said bearing.

2. Apparatus as defined in claim 1 and wherein said shaft comprises:

a reduced end portion; and

pilot sleeve means rotatably mounted on said end portion.

3. Apparatus as defined in claim 1 and wherein pressure arm has an elongated slot therethrough and said fulcrum means comprises:

a rod projecting through said slot;

first means on said rod engaging one side of said pressure arm;

second means movable on said rod and resiliently biased against the other side of said pressure arm;

a segmented sleeve surrounding said rod;

means acting resiliently to contract said segmented sleeve;

means for expanding said segmented sleeve for engagement with an opening.

4. Apparatus as defined in claim 1 and wherein said screw means comprises:

a screw member threadedly engaged in an opening in said arm; and

a shoe connected by a ball and socket joint to said screw member.

5. A reamer apparatus for use in removing weld metal from the ends of boiler tubes or the like in a tube sheet, said apparatus comprising:

a pressure arm presenting spaced fingers at one end, having an elongated slot in the mid-portion thereof, and having a threaded opening at the other end;

a ring pivotally mounted to said arm between said spaced fingers;

a shaft rotatable in said ring and presenting a first shoulder toward said ring;

a thrust bearing disposed on said shaft between said shoulder and said ring;

a reamer element carried by said shaft for cutting engagement with weld metal at a tube end;

said shaft comprising a pilot end portion insertable into a tube from which Weld metal is to be removed;

a rod extending through said slot at selectively adjustable positions therealong, and having a threaded portion insertable into the opening of a tube other than the one from which weld metal is to be removed;

fulcrum means on said rod and engaging on side of said arm;

spring biased means engaging the other side of said arm and urging the latter against said fulcrum means;

expansible means mounted on said threaded end portion of said rod and expansible by rotation thereof to frictionally anchor said rod in said opening of a tube; and

feed screw means threadedly engaged in said threaded opening, said feed screw means being operative against a tube sheet when the apparatus is in use to apply feed thrust through said arm and thrust bearing to said shaft and reaming element.

6. Apparatus as defined in claim 5 and wherein said shaft comprises:

a reduced end portion; and

pilot sleeve means rotatably mounted on said reduced end portion.

7. Apparatus as defined in claim 5 and wherein said feed screw means comprises:

a screw member having one end configured to receive a drive wrench; and

a shoe connected by a ball and socket joint to the other end of said screw member.

References Cited by the Examiner UNITED STATES PATENTS 766,713 8/1904 Loetzer 772 1,781,338 11/1930 Moen -125 1,882,689 10/1932 Albertson 772 2,004,228 6/1935 Storm et al. 772 2,026,821 1/1936 Cleveland et al. 9012.5 2,749,809 6/ 1956 Anderson 9012 WILLIAM W. DYER, Jr., Primary Examiner. 

1. REAMING APPARATUS COMPRISING: A PRESSURE ARM HAVING A BIFURCATED END; A RING PIVOTALLY SUPPORTED IN SAID BIFURCATED END; A SHAFT ROTATABLY JOURNALLED IN SAID RING; A THRUST BEARING ACTING BETWEEN SAID SHAFT AND SAID RING; A REAMING ELEMENT CARRIED BY SAID SHAFT FOR ROTATION THEREWITH; FULCRUM MEANS ADJUSTABLY POSITIONABLE ALONG SAID PRESSURE ARM BETWEEN THE ENDS THEREOF AND INCLUDING EXPANSION MEANS FOR ANCHORING OF SAID FULCRUM MEANS IN AN OPENING; AND SCREW MEANS OPERATIVE ON THE END OF SAID PRESSURE ARM REMOTE FROM SAID BIFURCATED END FOR SUPPLY FEED THRUST TO SAID SHAFT THROUGH SAID BEARING. 